Monthly Archives: August 2011

There is a mission in the first Splinter Cell computer game where you have to use your thermal vision to read a keypad code entered by a guard. Researchers from University of California San Diego have now shown that this is entirely possible.

Building on earlier work by Mike Zalewski the researchers have shown that codes can be easily discerned from quite a distance (at least seven metres away) and image-analysis software can automatically find the correct code in more than half of cases even one minute after the code has been entered. This figure rose to more than eighty percent if the thermal camera was used immediately after the code was entered.

The major advantage of the Kinect is that it works in 3D. Previous console vision systems (such as the PlayStation’s structured light” created by a beam of infrared laser light passing through a diffraction grating. This projects a grid of 50000 infrared dots across the playing area. These infrared dots are visible on many cameras with a “night vision” mode.

By comparing how the dot pattern looks, and how it should look, the Kinect can measure the distance between the sensor and the player – producing a “depth map” in the process.

Images from Matthew Fisher. Objects in red are closest to the screen; colours then move through the spectrum to purple objects that are furthest away.

I only recently discovered the permil (cf. percent), a typographic character that enables you to give a fraction equal to one part in one thousand without using a decimal point. For example 12.3% = 123‰ (“twelve-point-three percent is equal to one hundred and twenty-three permil”).

There is also a symbol (‱) for basis points (aka permyriad), parts in ten thousand. For example 12.34% = 123.4‰ = 1234‱ (“twelve-point-three-four percent is equal to one hundred and twenty-three-point-four permil or one thousand, two hundred and thirty-four basis points”).

A large number of fonts are unable to render the permil and/or basis point symbols correctly, so the post above may be missing some symbols.